Is it possible to backup Guest webpages(available under ClearPass Guest >> Home » Configuration » Pages » Web Pages) through backup taken only from Guest (Home » Administration » Import Configuration » Import Configuration)?
No, it is not possible.
The backup taken from ClearPass Guest (Home » Administration » Import Configuration » Import Configuration >> Create a customized backup >> using Complete/Custom backup mode) does not include webpages created under ClearPass Guest >> Home » Configuration » Pages » Web Pages.
Guest backup/restore are legacy backup framework and are depreciated. Guest backup options was used for very old version of cppm-guest. These options are still there for some old customers who took backup in older version of amigopod (cppm-guest).
Incase the backup of webpages are required, CPPM backup/restore is the recommended backup option.
To take the complete server backup, navigate to ClearPass Policy Manager >> Administration » Server Manager » Server Configuration >> Select the server and click on Backup.